I'm afraid that I may have a blown head gasket, but I'm not to sure. Here's what happened.

A week ago the alternator completely froze on a trip. We had it towed and I replaced the alternator and serpintine belt, and it seemed to work fine after that. Then four days ago I was in a parking lot with the van idling, and I noticed that the voltage gauge was showing 8 volts. Before I could do anything, the engine died and the van wouldn't start. We jump started it and it started running fine again (after a few minutes).

Then finally, two days ago, my wife was driving home, and the van started to run a bit warm (about 3/4 of the way up). She tried to drive a little further to get to a place to pull over and it started to overheat more. It got about to about the "L" in "normal", was making a loud "dunk-a-dunk noise, (sort of like water on metal) and died. She pulled over and there was steam coming from the engine, but no smoke from the back. We then had it towed to a safe place and let it cool off.

I had my wife start it up to see what was going on. I could see it was leaking coolant from behind the alternator but I wasn't sure where from. I looked underneath and it wasnt coming from anywhere else. I had her shut it off and I checked the oil and there was NO water in it. I eventually figured out that a heater hose had blown, one leading from the heater to the water pump. We replaced the hose. Also the thermostat. I don't think it matters much at this point but in pulling everything apart we knocked off the oil-filler hose that comes off the pipe, and left it off until we were done. We put everything back together and filled up the radiator and started it up.

At this point it was running rough, and started to overheat. We shut it off and, thinking we just had an air bubble in the system, opened up the radiator and coolant went everywhere. We let it cool down and added more coolant- it took a lot more. We then started it up again and there were small puffs of white smoke coming out of the tail pipe. There was also a steady stream of coolant coming from the muffler. I checked the oil and there was water in it. Deciding that we could have flooded the exhaust system and gotten water in the oil-filler hose, we changed the oil, let it sit open for a little while and tried again. It was still running rough, still oil was coming from the muffler, and after one minute- more water in the oil.

We then decided to try to make it home to work on it there. On the way home, there was a lot of white smoke, but the oil pressure stayed perfectly normal. after about 1 1/2 miles it started to overheat. We shut it off, added more coolant and went for another few miles, limping it home and adding water one more time. Finally, the temperature was rising and falling, and the oil pressure still never moved. Sorry this is so long but Im not sure just what is going on. Any help would be great.

 

M Tucek,
Sorry to hear about your problems. It does sound familiar though. I've got a 94 4.0l in the back yard waiting for head gaskets. It acts very much like yours. Mine doesn't have coolant coming out the tailpipe though. I ended up buying another Aerostar and do the head job later. I suggest you do a search on head gasket in the Aerostar forum. You might find some information that will be useful.

Good Luck

 

Might just be a loose lower intake manifold, but with the amount of coolant in the exhaust, it could just as well be a blown head gasket. What year and engine size is your van?

 

It is a 93, 4.0. anything other then a blown head gasket is worth a try tho- cause I will probably have to replace the whole engine if it is. Do you know how to check if it is the intake manifold?

 

I only mention intake manifold as I am currently dealing with a less severe case than yours, of unexplained coolant loss. Other contributors suggested checking for loose manifold bolts as the earler 4.0 were prone to this. None of mine turned out to be noticeably loose but after re-torquing, and two days driving, there is no longer the engine stumble and mis-firing I was experiencing earlier. It is too early to tell if the coolant leak is cured as a result of this.

I could not decide how to check beforehand if it was the manifold vs head gaskets, but just decided to try re-torquing and see what happened. Getting the upper manifold off is not that difficult, once you figure out how to attack it. There was no cost involved, only time - about 6 hours. Let me know if you decide to pursue this and I can offer a few tips on the process.

 

I am definitely going to try this- like I was saying, the only other thing we could do is to buy a new engine. Any tips would be REALLY appreciated. We just dont have the money right now for a new engine (although I could do it myself). thanks so much.

 

Given the severity of your leakage, you may want to pick up a set of intake manifold gaskets (upper and lower) beforehand. With all the trouble it is to get to the lower manifold the few dollars for gaskets is inconsequential and good for peace-of-mind. If not used, you can always return them for credit.

I found the manuals to be less than useful and would suggest the following:

1.Disconect negative battery terminal (13mm)
2. Remove the air cleaner box and tunnel (5/16 and 7/16)
3. Remove the serpentine belt and alternator (13mm)
4. If equipped with A/C, undo the 4 mounting bolts(10mm) and allow the compressor to rest against the front bumper and grill, protecting the grill/bumper with padding. Support the compressor with a wire to keep the pressure lines from pulling on the spring lock fitting on the accumulator/drier.
5. Remove the weather shield on the throttle body (5/16") and using a small screwdriver, pry the throttle cable fitting from the throttle body linkage. (Snaps over a ball fitting)
6. Remove the 3 bolts (13mm) holding the coil pack to the intake and the exhaust manifold. The bolt on the exhaust manifold can best be reached by removing the wheel from the passenger side.
7. Remove the plug wire from the center cylinder to access the bolt with a 13mm box-end wrench. Pull the coil pack toward the fender and wire back out of the way. Unhook the plug wires from the wire loom on the back of the manifold through the passenger compartment engine access cover.
8. NOTE WELL! There is what appears to be an ordinary vacuum line coming from the left of the throttle body that goes back under the upper manifold and re-appears attached to a fitting on the right, lower side of the throttle body. DO NOT PULL ON THIS TUBING. Way back between the upper and lower manifolds is the purge valve solenoid from the carbon cannister. The tubing connecting all this is NOT flexible but rigid. If you pull on the tubing expecting it to be flexible, you will snap off the plastic connection on the solenoid valve and there is no way to fix it. (Trust me on this, I tried everything and wound up having to replace it.) Remove it by disconnecting the short, flexible bit of tubing from the throttle body first. Very carefully work the tubing from between the manifolds to expose the cannister purge valve. Use your left hand to "feed" the tubing coming in from the left side of the engine as you go along. I you encounter any resistance, stop and examine. It is dirty back there and hard to see what is going on. The two rigid tubings connect turkey-wishbone-style to fragile plastic connectors and will snap just like the wishbone.

9. Sketch the location (runs over this and under such-and-such component) and mark with tape the vacuum lines and sensor connectors attached to the upper intake manifold.
10. Remove the bolts holding the transmission dipstick and oil dipstick to the manifold (10mm)

At this point you are ready to remove the upper manifold. This is held on by 6 nuts. Having a small trouble light will aid in visualizing the nuts although a deft sense of touch will also help.
There are spaces between the intake runners to allow access to the two nuts on the right(driver's side) of the manifold. The best way to access these are with a 15mm deepwell socket on a 3 inch extension and 3/8in ratchet. I would highly recommend finding a small, strong magnet that will fit inside the deepwell socket. The advantage of this arrangement will be obvious when you attempt to replace those nuts.

11. Remove the 6 retaining nuts on the upper intake manifold, lift to clear the mounting studs and carefully pull toward the front to remove.
12. USE CLEAN RAG AND COVER OPENINGS ON LOWER INTAKE MANIFOLD! Last thing you want is a nut falling into the engine.

Check the 8 mounting bolts on the lower intake manifold to see if they are loose with 13 & 15mm sockets. The foremost and hindmost fasteners are nuts on studs while the interior 6 are bolts. Tighten starting with the inside most bolts working to the outside.

If you decide to go on and remove the lower manifold, you will be on your own at that point. This is as far as I have gone with my repair efforts. There is a technique to replacing the lower intake gasket and you would need a manual for the procedure.

Reassembly is essentially the reverse. Take notes as you go along, they are helpful when trying to remember where everything goes. You may also encounter a vacant connector near the temperature sending unit. This is normal. Mark it as such or you will go nuts trying to remember where it went.

Best of luck!

 

thank you so much- i will let you know how it goes and write if I have any questions.

 

great directions aero !!. i copied them and put them in my haynes manual for future referrence. yours were much clearer!. lately i've been looking around back in there for a small antifreeze leak on the intake manifold at the rear., , . you laid out the territory very well. ever think of writing your own manual? rick

91 aerostar xl ext. aka "the green been"
4.0 litre 187 thou. mi. and going.......

 

aero- having a little problem. I decided to do a compression check on the van to try and see if it in fact was the intake manifold before I spent a day and $80 + just to find out I needed to replace the engine. I finally got ahold of a comression gauge and cant seem to get a good enough seal on it to get a reading. Does it have to be sealed well? Is there a trick or special tool I need to do this on the van? Also- In removing the spark plugs and cranking the engine I realized that coolant is shooting from one of the spark plug holes and seeping from another. Could this possibly be a clue as to what the problem is? thanks!

 

M Tucek......

Blown Head Gasket.

Yours is doing the same as mine.
I'm going to do a complete rebuild on mine.

 

M Turcek,
I think JTHill24 is your man from this point on. Perhaps you two could collaborate on a tech article for FTE about head gasket replacement for the Aerostar.

Sorry about the gasket - rotten luck!

 

Just picked up a heavy-duty A-Frame and Chain Hoist to pick-up the body high enough to clear the engine.
I'm going to drop the motor with the trans still attached.
Looks like it will be easier in the long run to do that.
Still have to finish making the dolly to sit the motor & sub-frame
on before I lift the Body up.
Have read the manual 3 times so far on how to take it out and more than likely 3-4 more times before I get to dropping the sub-frame.

Like my Dad always says "Measure Twice, Cut Once"